1. _Temperature._--The mean temperature of Hertfordshire, as deduced
from the above observations, is 48.3°. It has varied from 47.0° in 1887
to 50.2° in 1898. The mean daily range is 15.9°. It was the least
(14.2°) in 1888, and the greatest (18.1°) in 1893. The mean temperature
of the seasons is as follows: spring 46.6°, summer 60.2°, autumn 49.2°,
winter 37.2°. The warmest month is July, with a mean temperature of
61.0°; the coldest is January, with a mean of 36.1°. August is very
little colder than July. In these two months only has the temperature
never been below freezing-point (32°). In December and January only has
it never exceeded 62°. It increases most rapidly during the month of
May, and decreases most rapidly during September and October.

2. _Humidity._--The relative humidity of the air, that is the amount of
moisture it contains short of complete saturation which is represented
by 100, is, at 9 A.M., 82. It has varied from 78 in 1893 to 85
in 1888 and 1889. The air is much drier in spring and summer (78 and 75)
than it is in autumn and winter (86 and 89). There is the least amount
of moisture in the air from April to August (74 to 78), and the greatest
from November to January (90).

3. _Cloud._--The mean amount of cloud at 9 A.M., from 0 (clear sky) to
10 (completely overcast), is 6.7. It has varied from 6.0 in 1893 to 7.4
in 1888. Spring, summer, and autumn are about equally cloudy (6.5 to
6.6), and winter is considerably more so (7.2). The sky at 9 A.M. is
brightest in September (6.0) and most cloudy in November and January
(7.5).

4. _Sunshine._--At Berkhampstead only have records of bright sunshine
been taken for the whole of the twelve years. Throughout the year the